An allergy test produces a single numeric score which contains the information about all the allergies the person has (that they were tested for).
The list of items (and their value) that were tested are:
- eggs (1)
- peanuts (2)
- shellfish (4)
- strawberries (8)
- tomatoes (16)
- chocolate (32)
- pollen (64)
- cats (128)
So if Tom is allergic to peanuts and chocolate, he gets a score of 34.
Write a program that, given a person's score can tell them
a) whether or not they're allergic to a given item, and b) the full list of allergies.
allergies = Allergies.new(34)
allergies.allergic_to?('chocolate')
=> true
allergies.allergic_to?('cats')
=> false
allergies.list
=> ['peanuts', 'chocolate']